The tombs were found in Xinjiang's Taxkorgan Tajik Autonomous County, a border region neighboring Afghanistan and Pakistan, China's state-run Xinhua news agency reported Tuesday.
Located on a crossroads of the ancient Silk Road, the tombs have been dated to about 2,500 years ago, or 300 years before China's first emperor established the Qin Dynasty (221-207 B.C.)
Eights tombs, each 6 feet in diameter, were arranged on a 100-yard by 50-yard platform, with lines of black stones and lines of white stones stretching alongside like sun rays, the archaeology team with the Chinese Academy of Social Sciences said.
"The ray-like stone strings might imply sun worship. No similar ones have been detected before in all of Central Asia," team leader Wu Xinhua said.
The people buried in the tombs might have been of high social status, the researchers said, because the black stones lined up with a certain pattern were a rare resource in the area and were likely carried to the tomb site from afar.